active/passive solar

We're getting ready to buy and build, and are curious about solar energy in Mexico. The houses that we've seen don't seem to use active solar at all, except for perhaps a little passive solar (shade curtains, etc.)

If anyone has built active solar into a house in Mexico, I'd be very grateful to learn any details, construction techniques, ease and general cost of finding materials, and whether you had a difficult time finding knowledgeable installers.

Re: [chrisnmarta] active/passive solar

We have recently acquired a life-time lease on an 80-acre ranch way outside of town. Definitely "off the grid" in popular solar speak.

Anyway, we are studying various solar devices and techniques, both active and passive. We have only gotten pricing info for equipment from the US and it is horribly expensive for the upfront costs. Suspect it would cost even more here in Mexico. Way beyond our retirement budget.

When we build we will incorporate as much passive technology as possible, facing the longest side of the house to the south, building under shade trees near a small creek, insulating well the roof and walls but allowing for lots of fresh air when the weather is right, black cisternas for passive solar hot water storage on the roof.

We have also lived in Mexico long enough to wean ourselves almost totally from high energy electrical appliances. No dish washers, powerful stereo systems, whole house vacuums, hair dryers, irons, clothes dryers, microwave ovens. When we move to the ranch we will also leave behind our 110 window unit A/C and go back to using evaporative water coolers, the norm in our area of the country.

Many of the neighboring ranches in the area use windmills and Hubby is looking into wind power for generation then storage of electricity in 12-volt deep cycle batteries. We are also planning to buy a number of small solar devices each with its own power arrangement, such as outdoor security lights and a terrific solar oven which will cook at temps up to 600 degrees. Much of our land is open pasture, treeless and rolling. It gets very hot here in the summers and there is lots of direct sun. Also pretty steady breezes. So we have options to explore.

Other ranches in remote locations depend heavily on butane gas, which is used all over Mexico for cooking and water heaters and is readily available. Many have butane refrigerators and have also converted their farm trucks to burn butane as fuel. Last week I even saw a butane-powered commercial floor polisher being used at my local Soriana! No cord to trip over.

As we finalize our plans and actually begin building, I will post more on our choices. Since we will be doing the work ourselves, hands on, not using subcontractors, we will keep everything as simple to install as possible.

Re: [Carron] active/passive solar

One thing I can comment on is the hydraulic ram water pump. If you have a year round stream and enough fall upstream, you will be able to use one of these pumps. It requires absolutely NO power of any kind except a stream with the required elevation factors.

Re: [chrisnmarta] active/passive solar

For warm water we are using two panels ( 2 x 2.7 square meters) together with a 300 l insulated tank. Price was 18,500 MXP, installed. For 2 persons this system works perfectly, we do not use additional gas heaters.

Our swimming pool is also warmed by solar panels POWERMAT panels are manufactured in DF. For more info go to www.imprema.com or to www.powermat.com. They have knowledgable installers all over Mexico.

Re: [Karin] active/passive solar

Re: [Esteban] active/passive solar

We have an established pond, about 3/4 acre and 5 feet deep, with fish and turtles right in the middle of the semi-desert. We don't yet understand the details of water access. There is a small "channel" as the owner calls it, about 2 feet wide and 1 foot deep coming from somewhere into our pond. It has been there for a long time because there are "los alamos" or tall old cotton wood trees lining the banks. (We plan to build under those trees.) When there is water in the channel it tumbles vigorously into the pond. At other times the channel is dry.

The owner says we have to purchase an annual water permit which costs 1800 pesos per year to have some bureaucrat turn on the water from a distant dammed lake for 24 hours 6 times each year. Suggestion is that same official will turn on the water for more hours if given a tiny mordida. Hello?

Thank goodness we also have a deep, stone-lined well which seems to flow regardless.

Re: [Carron] active/passive solar

You may have a problem with having the water turned on by the water official for a mordida. Why? Unless you are first inline from the source, the water will have to go through other pieces of property before yours, and that's when those people will see the ditch flow and wonder what's happening. In the desert, water is gold. You need to check if this water is flowing through ag fields that are using fertilizers or insect sprays.

Re: [Esteban] active/passive solar

Right. In the West, Southwest, and Mexico (as in most places) the most important question you can ask is "where does the water come from?" and the most important information you should get is the answer to that question.

Re: [Esteban] active/passive solar

I am still puzzled by how the water actually reaches our property. But when we have visited the ranch we have seen the individual ditches to ranches farther from the lake than we are running with water while ours is not. Very little farming on any neighboring ranches, except for the occasional corn patch, just pasture land for horses and some cows. Hope there will be no ag pollution problem. The pond is well established and has been in use for several generations. The water is filled with fish and turtles and fresh water mussels (clams?) and frogs, so I assume it is pretty chemical free. At least I haven't seen any mutations yet!

Re: [Carron] active/passive solar

You have to have water to sustain life. If I were you, I'd find out EVERYTHING possible about your water situation. If you can't get adequate water, you won't be able to survive. It's the most important aspect of infrastructure in any building/construction project. You can live without everything else except water. If you look at the history of the Baja, for example, there were communities that were formed only to disappear because of lack of water.

Re: [chrisnmarta] active/passive solar

Solar Energy. When we first built part of our house in 1995 in Tankah, on the Caribbean coast near Tulum, we had no electricity. We had a neighbor that sold and installed solar that he imported from the states. We expanded tha house to what it currently is and used the solar for a few more years until the "new" people in the area got together and brought in the CFE power. For solar we had 4 -75 watt panels and 12 batteries that supplied a house of about 1800 sq ft. We had propane refrigerators that worked great, we had 24 volt system and used small DC water pumps to pump water from our shalow well to the cistern and from our cistern to the tenacos on the roof (which was equivalent to being on the 3rd level up). We had no TV, microwave, A/C, hair dryers, or laundry equipment at that time but could have used all but A/C if we wanted to add more panels and/or batteries. We had to be careful with power usage, but not so much that we couldn't use the ceiling fans all night when needed or use the cd player or laptop. Batteries should be of the golf cart type so they can drain down and recharge w/o a problem but we couldn't get them easily so we used truck batteries and they worked fine as long as they didn't drain down too far. Neighbors had 10 panels but only 4 to 6 batteries and always ran out of power. Our 4 panels were sufficient because the gas tank, (i.e. the 12 batteries), was large enough to store plenty of power. Solar requires some battery maintenance, is very expensive up front, and really doesn't give enough for the modern household unless your system is hugh, or you do w/o like we did. I used a dealer once in Cancun for a some equipment and got ripped off when he didn't come through with all we purchased. I'm sure you can get solar much more readily in Mexico now from dealers in Monterey or other large cities. Look for good brands like BP or Kyocera for panels, Trace for inverters etc. Now we are "on the grid" and I have to admit it is a lot easier. Stan http://CasaTropical.comStan

Re: [Esteban] active/passive solar

Even as I write this, cold fresh water is gushing into my pond at Rancho San Gabriel! I admit it took us almost two weeks to figure it all out, with the help of the ranch owner, his mother (our current landlady), and my Spanish-speaking daughter.

Apparently, all the ranch owners in the area belong to an agricultural co-op. Fees are 3000 pesos per year. This can be paid in 3 installments, one per every 4 months. Somewhere running through the remote ranchlands is a central channel from the lake. It only has water in it when a ranch owner has requested water. Each individual ranch then has a smaller gated channel running from that main channel to the ponds.

We paid our fees for the rest of this year at an office in town several days ago. The order then went out to a man who lives on a ranch near ours to turn on our water. (Apparently this is the guy we can offer a bottle of brandy to leave the water turned on longer should we need it!) We had his cell phone number so we could coordinate with him since we have to be present for him to turn on the water. We were told that one of the ranches just above us was planting and that since it was a commercial operation, their water supply took precedence over our domestic pond in which we only raise fish and turtles and a couple of horses drop by for the occasional drink. Apparently only one ranch at a time can receive water.

He arrived about 11:00 this morning, almost on time, and all went just fine. He looked at our pond and made a rough determination of how many hours he would need to keep the water on to fill it to overflowing. When we left at almost sunset, the pond was ready for skinny-dipping and we plan to try it out tomorrow!

We now have phone numbers, account number, receipts, names, faces, and an idea about the entire process for future reference.

Re: [Carron] active/passive solar

Sounds great but I'd be VERY careful about taking water when you shouldn't be. The other "commercial farmers" may be very protective about the supply. You should also get the water tested for potential chemical residuals. It's doubtful the farmers are organic so you may get fertilizer and/or pesticides in your water that could cause harm to your family. Other than that, I bet a nice cool swim will feel great in this weather.

Re: [Marta R] active/passive solar

We're getting ready to buy and build, and are curious about solar energy in Mexico. The houses that we've seen don't seem to use active solar at all, except for perhaps a little passive solar (shade curtains, etc.)

If anyone has built active solar into a house in Mexico, I'd be very grateful to learn any details, construction techniques, ease and general cost of finding materials, and whether you had a difficult time finding knowledgeable installers.

Thanks!

What is the basic difference between active and passive solar panels? We are looking to install them so can you share out some vital and useful information? Waiting for reply thanks in advance:)

Re: [ChadBurns] active/passive solar

Actually solar panels are 'active'. Passive denotes using the sun's rays for warmth.... such as what comes in your window and warms up the room or in greenhouses, sunrooms and solariums -- as the sun's rays pass through the glass windows, the interior absorbs and retains the heat.

Re: [RickS] active/passive solar

There are many dealer/installers of PV Solar (electric) in Mexico. All major brands are available. Solar electric is not expensive in Mexico. Our area (Lake Chapala) has several hundred installations. Our dealer E2Engerias does work anywhere. I suggest you contact them gcorona@e2energias.com They are distributors for Sharp and Panasonic in this area of Mexico.

Re: [ChadBurns] active/passive solar

We're getting ready to buy and build, and are curious about solar energy in Mexico. The houses that we've seen don't seem to use active solar at all, except for perhaps a little passive solar (shade curtains, etc.)

If anyone has built active solar into a house in Mexico, I'd be very grateful to learn any details, construction techniques, ease and general cost of finding materials, and whether you had a difficult time finding knowledgeable installers.

Thanks!

What is the basic difference between active and passive solar panels? We are looking to install them so can you share out some vital and useful information? Waiting for reply thanks in advance:)

These two posts point to differing issues. "Passive solar" is solar collection of heat or light without running pumps, or fans, or other things that need energy from other sources (no electricity used). "Passive solar" includes trombe walls (to collect heat) where that heat is used either to heat a space or as part of a passive solar chimney. The trombe wall absorbs sunlight and then radiates heat for many hours. In cool/cold places, that heat is used to heat the home, while in hot climates that heat is used to make hot air that rises through a chimney. The rising air in the chimney is used to draw hot air off a ceiling and to draw cool air in from some vent that supplies cool air - like from a shady garden that has an air-cooling water-feature like a fountain or pond . The sun's heat from the trombe wall (up on the roof - or on an exterior wall) is used this way to create a gentle breeze of cool air in our rooms with no electricity.

Active solar means there is some outside power source (like electricity) that powers fans or pumps to move air or water.

Photovoltaic solar panels that generate electricity are their own special area, and are neither "active solar" nor "passive solar", when talking about designing or building solar systems.

This means that an active solar panel would be one that has an electricity powered water pump that circulates water through the panel to make hot water for the home. (or a fan that circulates air)

The most common passive solar panel would be one that has the panel's cold water supply inlet at the bottom of the panel - attached to the bottom (cool side) of a hot-water-storage tank. As the sunlight heats the panel, the water gets hot in the panel and rises. That natural rising of the sun-heated water pushes water out of the top of the panel into the top of the hot water storage tank - which pushes more cool water out of the bottom of the hot-water storage tank into the bottom of the solar panel - creating a natural cycling of water from the tank through the solar panel - gradually heating the water in the storage tank, with no circulating pump.

So, when talking about active and passive solar panels - we are talking about heating air or water - not generating PV solar electricity. ??? steve - Read-on MacDuff E-visit at http://yucalandia.com

Re: [Marta R] active/passive solar

We're getting ready to buy and build, and are curious about solar energy in Mexico. The houses that we've seen don't seem to use active solar at all, except for perhaps a little passive solar (shade curtains, etc.)

If anyone has built active solar into a house in Mexico, I'd be very grateful to learn any details, construction techniques, ease and general cost of finding materials, and whether you had a difficult time finding knowledgeable installers.

Thanks!

We've got both active and passive solar systems for heating the house and heating water. Our 40 gal - 1 panel - passive solar water heater does fine for our 4 small apartments here in Merida, but it is undersized if we have 3-4 consecutive cloudy days. Our 500 gal active, 6-panel, solar water heater does a good job of heating our Colorado home.

On the passive solar system, we have only Mexican tenants who are not taking ½ hour hot-hot showers and with rooftop plumbing, both hot and cold water supply pipes to the kitchens and bathrooms get hot during the day time (esp in the dark-green colored sectors). If you have people who want to take long hot-hot showers, you'd need a bigger capacity passive system. To determine how big a system is needed, you need to know the temperature of the inlet water and how many hours per day of insolation you have. Our ground water is about 78º F and roof-top tinaco stored water comes in at about 86º F - which allows us to use just a 40 gal passive system in sunny Merida - with infrequent periods of 3-5 cloudy days.

I've fooled around with passive-solar chimneys to suck out hot air, but we have few sources of cool air - so all our efforts there have been temporary - small-scale.

I'm tempted to try putting 10" PVC chimneys (painted black) on the 2 hot ceiling/roof points on our home, but that still needs a supply of cool air, and since the PVC does not have much thermal capacity - the chimneys would draw air only during the daytime.

Does anyone out there have experience designing and building passive solar chimneys - possibly including passive solar collection panels on the roof - to simultaneously shade the roof and to store heat, that's later used throughout the evening and night to drive a solar chimney.... building a solar-heated "hearth and chimney" on the roof - with vents that draw air through your living space from a cool space (like a natural cenote/cave or garden)? steve - Read-on MacDuff E-visit at http://yucalandia.com